The present invention relates to data processing systems and is more particularly concerned with systems which are suitable for operation in a multiprocessor configuration.
A multiprocessor system is one in which there is provided one or more processor modules, a common memory having one or more storage modules and one or more input/output modules, for the handling of data transfers between peripheral equipments and the memory, together with an intercommunication medium for the passage of information between the memory and processing and input/output modules.
In a multiprocessing environment each processing module may require exclusive use of areas of the common memory. Because of the asynchronous nature of the processing modules, two processing modules, may demand access to the same area of the memory simultaneously and it is common place to resolve this clash of store demands by utilising a queue technique which locks the store exclusively to a single processing module for the completion of its Read or Write cycle.